You might find that there is some overlap between this question and the one previously asked. Rachel's drive as a food critic and food analyst allows her to create great masterpieces, critique them in areas that need improvement, and serve as a way to convey emotional satisfaction. Consider her preparation of potatoes in different forms to parallel the advancement of a relationship's stages. In the end, Rachel understands that the source of her "heartburn" might have little to do with pepper and spices added, but rather might be reflective of how she needs to find a level of emotional satisfaction within her own sense of being. The vastness of her intelligence and her material comfort will not be able to supplant this emotional component. Her emotional sustenance is lacking in that she might be seeking something perfect. Be it recipe or relationship, she understands through her challenges with Mark that either is impossible. For example, while she remarks at her strength for not surrendering her vinaigrette recipe to Mark, there is a tone that this is a hollow victory, representative of a lack of emotional happiness. In leaving Mark and understanding that food cannot be a substitute for articulated emotions, but rather a complement to them. Rachel begins to grasp that the drive for being merely happy, as opposed to being perfect in both food and love, will be critical in being able to establish a foundation of emotional sustenance.